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Register a new userEvidence for a disorder driven phase transition in the condensation of 4He in aerogels
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Added by
Pierre-Etienne Wolf
Publication date
2008
fields
Physics
and research's language is
English
Authors
Fabien Bonnet
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We report on thermodynamic and optical measurements of the condensation process of $^4$He in three silica aerogels of different microstructures. For the two base-catalysed aerogels, the temperature dependence of the shape of adsorption isotherms and of the morphology of the condensation process show evidence of a disorder driven transition, in agreement with recent theoretical predictions. This transition is not observed for a neutral-catalysed aerogel, which we interpret as due to a larger disorder in this case.
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